Glutathione-Sensitive Silicon Nanowire Arrays for Gene Transfection.

Ingenious surface modification strategies and special topological morphologies endow biomaterials interface excellent ability to regulate the cell fate. In this work, a gene delivery platform based on glutathione-sensitive silicon nanowire arrays (SiNWAs) is developed, exhibiting good transfection efficiency of several cell types. Briefly, the surface of SiNWAs is grafted of PEICBA, a branched cationic polymer cross-linked by disulfide bonds (SN-PEICBA). When cells adhere to the platform surface, silicon nanowires penetrate into cells and high concentration of reduced glutathione (GSH) in cytoplasm break the disulfide bonds (S-S) in PEICBA. The plasmid DNA (pDNA) preloaded on the cationic polymers is successfully delivered to the nuclei through the non-lysosomal pathway. Cells harvested from the SN-PEICBA show high retention of viability and the platform surface can be reused though S-S replacement for at least three times. In general, our platform is a creative combination of intracellular responsive strategy and surface morphology, which has great potential for auxiliary use in ex vivo cell-based therapies and various biomedical applications.